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On Monday, the clamorous animal rights group PETA announced it would award $1 million to the first person to come up with a way to make commercially viable in vitro meat by 2012. The fake meat would have to be indistinguishable from the real deal, according to competition rules, and it would have to be cheap enough to succeed in the marketplace.

In theory, this seems like an excellent idea, with the potential to ease the burden on the environment from meat production, reduce greenhouse gas emissions and improve human health. In practice, however, the chances of anyone actually winning the prize seem slim. "No one has yet produced [in vitro meat]. No one has succeeded in coming close," says Dr. Stig Omholt, director of Norway's Centre for Integrative Genetics and chair of the In Vitro Meat Consortium, which held its first symposium this month. Still, Omholt says, "it seems possible to develop this technology."

Scientists first began working with in vitro proteins, grown from animal cells in Petri dishes and bioreactors, about a decade ago. The technology was originally conceived as a means to make food for astronauts to take on long space missions; in 2000, the first edible in vitro muscle protein was created from a goldfish by the NSR/Touro Applied BioScience Research Consortium. Soon after, scientists realized the broader applicability of the technology and began developing it to feed the rest of us earthbound folk.

Here's how the process works: scientists biopsy stem or satellite muscle cells from a livestock animal, such as a chicken, cow or pig. The cells are then placed in a nutrient-rich medium where they divide and multiply, and are then attached to a scaffolding structure and put in a bioreactor to grow. In order to achieve the texture of natural muscle, the cells must be physically stretched and flexed, or exercised, regularly. After several weeks, voila, you have a thin layer of muscle tissue that can be harvested and processed into ground beef, chicken or pork, depending on the origin of the cells. But don't expect to see big, juicy in vitro steaks anytime soon; the technology has not yet been able to synthesize blood vessels or grow large, three-dimensional pieces of meat.

Though it sounds a lot like Frankenfood, scientists note that in vitro tissue engineering is not the same as genetic engineering, a common misconception. "We use natural cells from natural animals," says Dr. Vladimir Mironov, a tissue engineer and assistant professor at the Medical University of South Carolina. "We don't change Mother Nature, we just try to imitate it." But there's always room for improvement  scientists can design meat, for example, that is high in healthy fats, such as omega 3s and 6s. Creating the meat in a lab also decreases its exposure to bacteria and disease, which have riddled the livestock industry, injuring consumers and causing extensive meat recalls.

The technology to produce in vitro meat is almost in place, says Mironov, but "there are bottlenecks" in the process  namely scale and cost. Given the current technology, it would cost $1 million to turn out a 250g piece of beef. The problem boils down to producing a cell-culture medium in large enough quantities at a low enough price (it's the same problem facing tissue engineers who are attempting to grow artificial organs for human transplant). So, two weeks ago, an international group of experts assembled in Norway for the first In Vitro Meat Consortium symposium to talk about how to scale up the technology and sustain it long-term. The group concluded that it will be possible to produce in vitro meat in large quantities in the future, but not without funding to continue research. Scientists estimate that in vitro chicken could be produced for about double the current cost of regular livestock chicken, a price that would fall as the process becomes more efficient. "The consensus was that this is doable," says Omholt.

Doable, yes, but not by 2012. It will take at least five to 10 years of research, followed by an extensive approval process, to ensure that any in vitro meat produced is fit for human consumption. Though PETA's competition may not produce a winner soon, the hope among scientists is that it will create interest and funding. As for selling fake meat to the public, that's another matter. But then, in an era of artificial hearts and over-the-counter genetic tests, perhaps even meat from a test tube has a future.